Generic advice

Before starting the actual translation work it is advisable to read the Fordítás HOGYAN.
Learning to use the tools themselves is not a big deal, and you don't need to wait for permission from anyone to start contributing. But to make those translations count, you want to read this loooong documentation.
If you want to help finding problems with our existing translations, Transvision is a great QA tool to search and compare translations between English and Hungarian for desktop and mobile applications. Especially the Consistency view.